Airsense 11 Time Zone Change

[LindanHotAir]

The cell network distributes time from a Stratum 1 time base which is synchronized to the time base used by and transmitted from GPS satellites and is traceable to the NIST time standard. Resmed should use this facility available from cell networks worldwide to properly set the time and date in their machines.

[Millstone50]

My unit has been found to be off by about 3 minutes. It's mind-boggling that the device would not reference a proper authoritative time source. Even the DreamStations would sync when the modems were connected. I wonder how this can be corrected?

[Millstone50]

Official ResMed response: "The time on Air11 devices cannot be changed. These devices are connected to the time zone."

[ScottZZZ]

Are you sure they didn't say "Twilight Zone"?  That might make more sense...  

[pholynyk]

If ScottZZZ is correct in saying the error doesn't drift - his doesn't - then maybe there is a high precision RTC chip (Adafruit carries one) which isn't being set accurately at the factory.
I guess the designers never thought that users might want to synchronise strange devices that were NTP sync'd.
Lots of strange design decisions...

[ScottZZZ]

I have to worry about "compliance" right now, but...  If there is someone out there with an AS11, not concerned about compliance, and doesn't care about MyAir -- It would be interesting to put one in "airplane mode" for a couple months and see if the clock drifts. I've *assumed* mine is being periodically synced, perhaps via the MyAir upload connection, since it hasn't drifted since I started tracking it in November.

I'd normally dismiss Resmed using a more expensive RTC, though it wouldn't necessarily be a bad choice since some machines will be in locations where there is no cell signal.  But for that situation, based on squeezing out every penny of profit, I'd still expect Resmed to utilize cheaper chips and put a clock-change function into the UI.

[sleepypapy]

There is an option to change TimeZone in the ResMed myAir profile when you access it via web browser.
https://myair2.resmed.com/my-account > about me > change

May be this method could be tried before using the last option of deleting whole user data from the device and changing the TZ.

[ScottZZZ]

There is an option to change TimeZone in the ResMed myAir profile when you access it via web browser.
May be this method could be tried before using the last option of deleting whole user data from the device and changing the TZ.

I tried changing that when I first got my AS11.  Unfortunately, that setting only affects MyAir.  It does nothing for the machine itself or what is recorded to SD, and therefore doesn't help with OSCAR (or ResScan).   :-(

[thistle]

I'm brand new to CPAP (3 days) and found this thread when I realized my time zone was set to GMT +0. I tried to set it to -5 and got the error message. The next day I went to delete all my data so I could reset it, since I only had 2 days of data on the machine, and for whatever reason it was now displaying properly at -5. I have no explanation for it. I did not have an SD card in (just got that today to start using OSCAR). Maybe try checking it and trying to change it and checking again a day later.

I also can't figure out where to display the current time on the machine so I can correctly get the time offset in OSCAR. Where can I find that, if it's available? If not, how do you calculate it?

[ScottZZZ]

... I realized my time zone was set to GMT +0.  I tried to set it to -5 and got the error message.  The next day... it was now displaying properly at -5.  

... I also can't figure out where to display the current time on the machine...  Where can I find that, if it's available?  If not, how do you calculate it?

Welcome to the forum!

Last question first...  The current time isn't displayed anywhere in the machine menus.  The way I have calculated the offset is by looking at start/end of sessions compared to the movement data on my Viatom/Wellue Sp02 device, which is synced daily to ntp.  Looking at the graphs in Oscar, particularly at a time when getting out of bed and coming back, it is easy to compare the CPAP data start/stop to the Movement data on the Viatom -- thus providing an offset to enter into Oscar preferences to align them.  Of course if you are NOT trying to sync with another device, then a few seconds error isn't worth correcting.  But the time zone is often worth correcting, particularly if the error splits your sleep session across noon.

Regarding the time zone display...  The menu doesn't always display it correctly.  Most often, the menus display +0 no matter what is actually set.  The most reliable way I have found to see the actual time zone setting is to view the "./SETTINGS/CurrentSettings.json" file written to the SD card.  That contains the current time zone, for example mine includes '"TimeZoneFeature":{"TimeZoneOffset":"-08:00"}"'.